My daughter is getting married next summer, and instead of a conventional wedding list would like to invite guests to contribute towards buying roof-top solar panels. Is it too unconventional to be acceptable? What other 'green gifts' would readers recommend?

I must confess that I am surprised this is even a concern. If couples can ask for cappucino throthers and ice cream makers, I don't see anything wrong with asking for contributions toward solar panels. In fact, in doing so they are doing us all a favor.